The answer to the question of how to make money on the Internet will depend on what you expect to obtain from it. If what you are after is some extra money, this is the best option available to you, because in it you will find jobs which do not take up much time and that will provide you with significant extra income.
This way you are able to do many things, from reading email to filling in opinion surveys. By recommending the site and the job to other people, you may start to form a work group, and you will be paid a commission for every person that is part of it.
If you are good at languages and wonder how to make money on the Internet, you can do translations or proofreading; this is also a valid idea to apply in your own language since you could correct the grammar and spelling of texts to be published.
Launching a company through the web is another way of making extra money on the Internet, and one of its biggest advantages is that this medium will open up the doors for you to trade in other countries, thus making a wide network of contacts, customers and, of course, profit.
For example, an online company that deals in flower, bombon and chocolate and presents delivery allows people who live abroad to send their loved ones presents only by going online and choosing a present from a catalogue. This way, they can be present in important social as well as family occassions by sending a thoughtful gift.
This is only one example of how to make extra money on the Internet, it is up to you to figure out which would be the best way for you to make extra income at very low cost and focusing mainly on the online market. The opportunities are at hand, all you need to do is reach out for them.